The present invention relates to a vehicle control system. More specifically, the present invention relates to a method and apparatus to control the powertrain of a vehicle.
Presently, speed and torque (power) control for many different types of internal combustion engines (ICEs) is provided by throttle plate control. A throttle plate is a control device coupled with an intake manifold in an engine to control the air flow through an engine. An ICE may be characterized as an air pump such that at any RPM the mass flow rate of air into the ICE varies directly with throttle plate position. As a driver depresses an accelerator pedal in a vehicle, the throttle plate moves to allow more air flow into the ICE and thus more power. A controller regulates the fuel supplied to the ICE as a function of the air flow. Typically, the air/fuel mixture is controlled to stoichometry.
The present invention is a method and apparatus for controlling the torque of an internal combustion engine utilizing electronic throttle control (ETC). The present invention is designed to be integrated into a coordinated torque control system (CTC) to improve the modularity, robustness and performance of an engine control system.
The present invention includes a series of software control modules contained in an engine or powertrain controller, although other vehicle controllers are considered within the scope of the present invention. The software control modules directly or indirectly control the position of an electronic throttle to improve the torque control accuracy for transient and steady state conditions, reduce engine to engine variation influence on system performance, and reduce calibration time. The present invention is able to accurately estimate the engine state and torque under varying conditions.